The prior art discloses conventional safety apparatuses for elevators which use electrical or electromechanical contacts and switches in order to determine the locking or closing state of an elevator door. Travel of an elevator cab should in this case only be permitted when all of the doors are locked. If, for example, an elevator door is blocked and cannot be closed, the cab should also not be able to continue its journey. In order to achieve this, in the case of conventional elevator apparatuses, the corresponding electromechanical switch at the door opens a contactor, which is connected into the working circuit and therefore directly interrupts the drive by virtue of the power supply to the drive motor or the drive circuit being interrupted by the contactor, for example.